Fluid lift



July 4, 1939.

JK. D. NIXON 2,164,469

FLUID LIFT Filed June l, 1957 2 Sheets-Sheet l July 4, 1939.' J. D. NlxoN 2,164,469

.FLUID LIFT l Filed June 1', 1957 2 sheets-sheet 2 l de@ D. N/xon.

ation of the valve is Patented July 4, 1939- UNITED STATES J eddy D. Nixon,

FLUID LIFT Houston, Tex;,

assignor of onehalf 'to Wilson Supply Company, Houston, Tex.,

a corporation of Texas Application June 1, 1937, Serial No. 145,680

1 Claim. (Cl. 10S-233) This invention relates to new and useful improvements in means for liftingl fluid from wells. This application is filed as an improvement on my copending application, filed February 1, 1937,. Serial No. 123,444, patented October 4, 1938, No. 2,132,081.

One object of the invention is to provide improved means for controlling the admission of pressure uid into a well tubing to lift the well liquid therein; whether the pressure fluid is supplied from the well or from an outside source.

Another objectof-the invention is to provide improved means for introducing gas or air under pressure into a well tubing at a single point below the standing liquid level therein, and so arranged that a simple and very eflcient installation is had, whereby the exibility of the device readilyI permits the invention to be installed at various installations to meet the different requirements necessary. Y

A further object of the invention isto provide an improved valve structure for controlling the admission of the pressure fluid into the well tubing, whereby standing, clogging,`or faulty actueliminated, and efiicient operation thereof is obtained.

A construction designed to carry out the invention will -be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in which an example of the invention is shown, and wherein:

Figure 1 is a` diagrammatic view of a well unit constructed in accordance with the invention;

Figure 2 isl a similar view showing a modified installation; f

Figure 3 is a diagrammatic view showing a modified installation of a well unit;

Figure 4 is a longitudinal, sectional view of a portion of the well tubing showing the uid inlet valve in an open and closed position;

Figure 5 is a horizontal, cross-sectional viewv taken on the line 5-5 of Figure 4;

Figure 6 is a similar view taken on the line 6 6 of Figure 4;

Figure 7 is a view partly in section and partly in elevation of a packer used in one of the modified installations of a Well unit; and

Figure 8 is a longitudinal, sectional view of a standing valve and nipple used in another modification of the installation of a 'Well unit.

In the drawings, the numeral fII designates the usual well casing (Figure 1) which has a well The tubing string extends substantially the full length of the casing I IJ, and its lower end may depend to within a short distance of the bottom of f the well, or it may be spaced at some distance therefrom. 'I'he lower end of said tubing is provided with the usual screen or perforated bull plug I3. In some installations it is advantageous to hold a pressure-on the oil sand and in such instances, of course, a suitable choke nipple I4 may be connected in the tubing above the bull plug near the lower end of said tubing. However, in

many cases, the nipple I4 may be dispensed with.

At a point above the choke nipple I4, an elongated collar I5 forming a valve `body (Figures 1, 4, 5,y and 6) is connected in the tubing string I2. An internal, annular chamber IGis formed in the valve body and has a number of inwardly directed radial guide ribs I'I extending thereinto. Also, an inwardly directed boss I8 is preferably formed integral with the collar and projects into the chamber. It is desirable, although not es sential, that the ribs and boss be spaced equally around the chamber wall. The guide rib marked I1' is preferably diametrically opposite the boss I8 for a purpose which will be described later.

A radial port I9' extends through the boss and Valve body and hasits inner end internally screwthreaded to receive a flanged nipple 20. The port is counter-sunk at 2| to form a shoulder against which the flange of the nipple abuts. 'I'he outer end of the bore of the nipple 20 is provided witl` internal screw threads to receive a plug or cap 2 I having an axial port 22 extending therethrough, to permit fluid to enter the nipple. The inner end of the bore of the nipple is reduced to form a valve seat 22', and a ball 24 is confined within the nipple and being so arranged to engage this seat 22' to close the bore of the nipple to prevent lflow therethrough.

The valve body I5 is provided externally with integral ribs or bosses 23 (Figures 1, 4, 5, and 6),

so that the valve body will be spaced from the casing and the outer end of the port 22 through the cap and 'nipple and `will not abutv or contact said casing, thereby preventing the accidental or undesirable closing or shutting oV of said port. As will be seen, this would prevent the entrance of a pressure iiuid from the casing into the tubing through the port 22. It is pointed out that a por- =tion of the periphery of the ball valve 24 in the cage 20 projects into the chamber I6 of the valve body I5, When the ball is seated at the inner end of said cage (Figures 4 and 5), an elongated, cylindrical Weight 25 is suspended from the lower end of a cable or wire line 26, which extends upwardly through the tubing I2 and through the casing head II at the surface of the well, and is movable vertically within said tubing above said bull plug. A suitable stufling box arrangement (not shown) packs off around the upper end of said tubing.

The weight ispreferably of suiiicient diam-r eter to contact the guide surfaces of all the ribs I1 and the boss I8, and it will be noticed in 'Figures 4 and 5 that, when the Weight 25 passes xthrough said valve body I5. said guide ribs I1,

and particularly guide rib I1', will force said `weight into contact with the concaved inner face pressure fluid will flow into-the tubing from the.

casing through the port 22 of the cap 2l in the outer end of the bore of the nipple 20 through said port and until the weight 25 is removed and the ball 24 allowed to contact its seat 22'. When said weight has been lowered or raised from the valve body I5, the pressure differential of the fluids in the casing and the tubing will cause the pressure fluid to flow through the port 22 into the tubing, thereby forming a suction around the ball 24 and drawing the same onto its seat 22 at the inner end of the bore of the nipple 20, thus closing theport I9 of the valve body.

In Figure 1, a typical installation ,is shown in which three starting or surface controlled valves I5 are mounted in the tubing string I2. However, it is pointed out that the number of starting valves used depends on each individual installation and vary accordingly. It will be seen that the invention is very flexible and can be adjusted to suit any well condition encountered. The various elements taken into consideration include the size of the tubing being used; the size of the casing in the Well; the liquid level in the well, that is, the level at which the liquid normally stands in the casing; the bottom hole pressure, that is, the pressure of the gas in the oil sand at the bottom of the well; and the 'amount of oil that is desiredto be removed from the well each day, or at each operation.

Air, gas, or other pressure fluid is introduced into the casing I through one of the pipes 21 of the casing head II in any suitable manner desired. It is preferred that a substantially constant operating pressure be maintained in the casing and any fluctuation therein prevented, although this is not essential as the invention will as readily operate if the pressure does not varyor fluctuate to too greatan extent. The Wire line or cable 26 may be operated by any suitable means desired.

In operation, the fluid level of the Well is ascertained and the valve bodies and other equip- -ment to be installed are made up in the tubing lower end of the choke nipple I 4, if the latter is used. The assembly is lowered into the well casing, until the bull plug or screen is at the depth at which it is desired to operate or produce from, preferably near the lower end of the casing I0 and at the upper end of the oil sand.

The weight 25, suspended from the cable 26, is inserted within the tubing and the upper end of said tubing closed as is the usual practice. The gas or pressure fluid is then introduced into the casing I0, and the weight 25 is lowered down into the uppermost starting valve I (Figure 1). As the gas pressure is built up in the casing I0, this pressure will be exerted upon the fluid level therein, so that the same is lowered by reason of the well uid being forced into the tubing I2 through the ports 22 and I9, around the weight holding the valve open and up in the tubing. As this pressure continues building up, the well fluid level in the casing is lowered until the well fluid level is substantially level with, or below, the port I9 of the valve I5, at which time the pressure fluid will enter said port and lift the fluid in the tubing up and out thereof. Thus, the operator at the surface of the well knows that the well fluid level is below the port I9 and then the weight may be lowered out of, the uppermost starting valve. The passing of the pressure fluid through the port I9, to lift the well iiuid in the tubing, will form a suction around the ball valve 24, which will draw said ball valve into its seat 22' in the inner end of the bore of the nipple 20, thus closing the ports I9 and 22.

The lowering of the weight is continued until the second starting valve is opened and the same operation is repeated until this valve is kicked olf, meaning the uid in the casing being forced into the tubing and then being raised and expelled therefrom, as described above. The well may be operated from this valve or any of the `other valves and if desired, the third or next starting valve may be kicked off in the same manner. Thus, it will be seen that by operating from any of the desired valves, any amount of liquid may be lifted as required to obtain the quota or proration set up for each well and it is an easy operation to change from producing oil from one valve to a higher or a lower valve in the tubing string.

The well fluid in the casing, below the port I9 of the valve being held open and the upper end of the bull plug I3, serves or acts as a packer or a closure means for the lower end of the casing, whereby it will be seen that a chamber for the pressure fluid is formed thereabove and the well fluid is free to enter the tubing through the bull plug and its entrance is facilitated by the pressure fluid entering the"'ab0ve mentioned valve and lifting said well fluid out of the tubing.

As the fluid in the tubing is lifted, the well fluid around and below the bull plug I3 and from the oil sand is now free to enter the perforations of the bull plug and to flow upwardly through the tubing and the chamber I6 .of the valve I5. It is pointed out that as the bottom hole pressure of the well is `suilicient to carry the well fluid up to the standing fluid level, the well fluid will be carried up past the starting valves I5, because all of said valves are preferably mounted below the standing fluid level. The pressure iiuid entering the starting valve, being held open by the Weight, from the chamber formed in the casing by the well fluid in the casing below said valve, will aerate the well fluid that when the invention is used in different wells,-

in the tubing above the valve being heldopen and will lift the same up and out of the tubing I2.

It is pointed that the fluid entering the tubing Lwill be lifted up by the pressure fluid, as long as one of the valves is held open. If it is desired at any time to shut down the well, that is, halt production, the weight is lifted or lowered out of the valve that was being held open. The pressure fiuid will close the port I9 in said valve by m'oving of the ball 24 onto its seat 22.

Suitable valves (not shown) at theupper end of the well may be closed; one of saidvalves will be in the flow line, so as to cut off the admittance of pressure fluid to the casing; and the other valve will be in the f-low line f the well fluid outlet from the tubing. With the upper end of the weil thus closed, the pressurel in the tubing and the casing will remain the same as long as lthe valves (not shown) at the upper end of the well and the valves I5 are closed. The assembly may be inoperative for any length oftime desired, because it is not possible for the pressure to escape and, therefore, a constant, built-up pressure is maintained in the casing and the tubing. However, when it is desired to again operate the well, the valves at the upper end of the Well (not shown) are then opened, and the weight 25 Ais either lowered or raised, so as to open'one of the surface controlled valves I5. The bottom hole pressure will again lift the well fluid above the valve being held open, and the pressure fluid now entering said port I9 in said valve will lift the well fluid up and out of the tubing, and the well is now producing as before.

In Figure 1, I have illustrated the various elements of the assembly, as mounted inthe ytubing string I2 and spaced apart; although, it is to be understood 'that the various elements have to be spaced in accordance with each individual installation, and the invention is n'ot to be limited to the number of starting valves shown, as a greater or lesser number'may be used. It is pointed out different conditions are present and, naturally, the invention will have to be modified to fit each individual installation. However, it is essential in all cases that the major number of starting valves I5, which have the ports I9 therein, and the bull plug I3 be below the standing fluid level within the well, and it is preferable to locate all of said valves below said uid level.

The usual practice oflifting well iiuid by pressure has been to introduce pressure at the bottom of the well, and thereby raise the entire column of uid in the tubing the full .length lof the well. There is a disadvantage to lifting fluid in this manner, as an enormous pressure is required to accomplish the same, and particularly to kick off, or` start the lifting of the well fluid. As illustrated by the assembly shown in Figure 1 of the drawings, the Well fluid is raised relatively a small amount at a timeand substantially a short distance, that is, in comparison to thelength of the well tubing, and consequently, the well fluid can be raised with a much smaller pressure, which results in a decreased operating cost. l

In many instances, the Well is operated only a limited period each day, and in such cases, it is desirable that the well kick off or flow immediately. With all of the present flowing devices now in common use, quite .some time is required to casing and the tubing has risen to the standing ing application is usually'employed in the various installations. Although, the device has been described as utilizing gas pressure, it is obvious that air or other pressure fluid could be employed.

rIn Figure 2, I have shown another modification or setting of the invention wherein, instead of the choke nipple I4 shown in Figure l, I have mounted a short nipple 30 having an axial passage 3| extending therethrough. The upper end of this nipple 39 is provided with a ball valve 32 mounted in a cage 33 and seating on an annular replaceable seat 34. This described structure is the equivalent of what is known as a standing valve or a check valve. The operation of this form of the invention is the same as has been described, and when the well fluid from the oil sand enters the bull plug I3 of Figure 2, it passes up through the axial passage 3I of the nipple 39, lifting the ball 32, and the fluid iiow thereabove. Upon any downward movement of said fluid or discontinuation of the upward flow, said ball 32 will drop into its seat 34, thereby closing the passage 3I through the nipple. Thus, it will be seen that the well fluid is trapped above the nipple and ball valve 32. This fluid is lifted and raised out of the tubing I2', as has been described for Figure 1. The operation of this form and the settingof the invention is the same substantially as has been described.

In Figure 3, a different form or setting of the invention is shown, which is particularly used under certain conditions encountered in oil wells of some fields. In some installations, it will be desired to use this setting of the invention. A suitable packer 36 (Figures 3 and 7) is connected in the tubing string, near the lower end thereof, in place of the choke nipple I4, or the standing valve nipple 30, and this packer engages the inner wall of the casing I0 to prevent flow through the space between said casi-ng and said tubing, whereby the' well fluid from the bottom of the hole is caused to flow upwardly through the tubing I2'. Although, any suitable packer may be used, I prefer to employ the packer disclosed in the drawings.

This packer, clearly shown in Figures 3 and 7, includes an upright, tubular mandrel 31, provided at each end with screw threads, whereby it may be readily connected in the tubing string. The upper portion of the mandrel is preferably connected to the lower end of a starting valve 38', similar to the starting valve I5, connected in said tubing string (Figure 3i." The lower portion of the mandrel is reduced and forms a shoulder 50 and carries an annular, inverted thimble 38, having its lip extending upwardly, and an elastic, cup-shaped, packing collar 39 has its lower end secured in the thimble, whereby the upper end or lip of the collar is left free to expand and contract said casing so as to' pack off the space between said casing and said tubing. An annular bushing 40 is mounted on the reduced portion of the mandrel and has its upper below the thimble to hold said thimblethereonclamp said packing" collar 39.

A suitable bull plug I3', similar -to the one' described, may be connected to the collar 42, as shown, or a short length of tubing (not shown) may be connected between said bull plug and said collar 42, if desired. The upper end of the mandrel 37 is connected into the lower end of the starting valve 38', so that when it is desired to pull the tubing string, a suitable bar, Weight, or other tripping mechanism (not shown) may be dropped down into the tubing string, thereby opening the port I9' of the valve 38'. The lower end of said bar will come to, rest within the bull plug I3' and its upper end will extend above said valve 38', holding this valve open until the packer is pulled from the Well and then this bar may be removed from the valve 38', packer 39, and bull plug I3 at the top of the well. Thus, it will be seen that the well fluid between the tubing-and casing above the packer is allowed to drain back into the tubing, down Patent is:

A well flowing assemblyT including, a well tubing within a well bore, a series of flow valves normally closed mounted in the tubing at successive elevations below the level of column of fluid standing in said tubing, a packer mounted on the lower e'nd of said tubing, one of said valves being positioned in close proximity to said packer, so as to serve as a bleed valve, a device mounted to be lowered in said well for successively engaging the flow valves and positively opening each of said valves, and a flexible connection secured to the device for rapidly raising and lowering the same in said well.

J EDDY D. NIXON. 

